1. Field of the Invention
The present invention relates to sugarless gums, including chewing gums and bubble gums, and more particularly to such gums that exhibit improved resistance to staling.
2. Description of the Prior Art
Chewing gums and bubble gums have been prepared in the past, with the purpose in mind of extending shelf life. Characteristically, gums prepared and stored, even at room temperature for extended periods of time, tend to lose their moisture and elasticity, with the result that they become brittle, and initially crumble when they are placed in the mouth. This problem is particularly noticeable in the instance of sugarless gums, and particularly those gums that are stored in a dry atmosphere, i.e. an atmosphere having less than from 50 to 60% relative humidity.
Sugarless gums conventionally contain on the order of about 5% of water, and it is therefore theorized that brittleness or the phenomenon of staling results from the loss of that water, due to evaporation or otherwise, over time. Specifically, most sugarless gums contain large amounts of sorbitol, which serves conventionally as a sweetener, as well as a bulking aid. Sorbitol is known for its tendency to recrystallize in the presence of even small amounts of water, and its tendency to crystallize when the water in which it is dissolved is removed. It is therefore theorized that, as the water containing the sorbitol in the gum composition, is lost by evaporation or otherwise, the sorbitol crystallizes and thus promotes the embrittlement of the gum composition, that contributes to the staling phenomenon. Thus far, the only workable approach to prolonging gum composition freshness relied on the use of fin-seal packaging with water vapor impermeable laminates to exclude all external ambient atmosphere and accompanying moisture and conversely to prevent the egress of moisture from the package contents. This approach is very costly and has its limitations, as periodic package leakage permits staling to occur unabetted as before.
A need therefore exists to develop a gum composition that is resistant to staling and thus offers improved shelf life, without the requirement for use of air-tight sealed packaging.